The work energy theorem is useful, however, for solving problems in which the net work is done on a particle by external forces is easily computed and in which we are interested in finding the particles speed at certain positions. Regarding the workenergy theorem it is worth noting that i if w net is positive, then k f k i positive, i. The kinetic energy of an object is a scalar value, meaning it does not depend on the direction the object moves in. Study material and notes of ch 11 work and energy class 9th science. For these two orbits, determine whether the kinetic energy of the satellite changes during the motion. Cbse class 11 physics chapter 6 work, energy and power notes in pdf are available for free download in mycbseguide mobile app.
Aug 22, 2017 working body losses energy, body on which work is done gains energy. Work energy theorem class 11 notes edurev is made by best teachers of class 11. Along the way, well talk about work, kinetic energy, potential energy, and conservation of energy. Work is done on an object when the object moves in the same plane as the. Energy, kinetic energy, work, dot product, and power. Apply the work energy theorem to an object that experiences a net external force. Work transfers energy from one place to another or one form to another. The work w done by the net force on a particle equals the change in the particles kinetic energy k e. Work, kinetic energy, workenergy theorem b1, ch5 sec.
Calculate the work done on an object and its change in energy. Read online workenergy theorem and energy conservation book pdf free download link book now. Cbse class 11 physics notes chapter 6 work energy and power. Download work energy power problems with solutions. W f\\times\ s where s is the displacement of the body. Learn exactly what happened in this chapter, scene, or section of work and power and what it means. Increase in kinetic energy of body work done by total force acting on it. For example, consider the following figure, according to work energy theorem, work done by all the forces change in kinetic energy.
F x ma x d v v v v axd ax 2 2 2 0 2 2 0 2 work done by the force energy. Engineering mechanics pdf notes em pdf notes unit v analysis of perfect frames analytical method types of frames assumptions for forces in members of a perfect frame, method of joints, method of sections, force table, cantilever trusses, structures with one end hinged and the other freely supported on rollers carrying. Energy, kinetic energy, work, dot product, and power 8. Pdf the galilean invariance of workenergy theorem, at an elementary mechanics level, has not been. In these notes a brief and simple explanation of all important topics is given which will help students make an. Pdf revisiting workenergy theorems implications researchgate.
Jul 25, 2019 work, energy, and power is an important topic from jee main jee advanced exam point of view. The work energy theorem can also be applied to an objects potential energy, which is known as stored energy. This oer repository is a collection of free resources provided by equella. This relationship between kinetic energy and work is called the workenergy theorem. An interesting case of the work energy theorem occurs when all the forces acting on a body are conservative.
A summary of the work energy theorem in s work and power. Work definition if an object moves in response to your application of a. Work done by a force in displacing a body is equal to change in its kinetic energy. The kinetic energy k of an object is equal to the amount of work that is required to accelerate the object from rest to a certain velocity, v. Work done by the force is equal to the product of the force and the displacement of the object in the direction of force. Energy transferred to the object is positive work, and energy transferred from the object is negative work. Energy associated with the state of motion of an object. Work, energy and power tuesday february 10th reading.
Relation between kinetic energy and the total work done on an object. The net work equals the mass of the object times the velocity of the object squared divided by two from velocity initial to. Review the key concepts, equations, and skills for the work energy theorem. Suppose a body is moving on a smooth horizontal surface with a constant velocity, u. The work done by the net total force on an object is. In grade 10, you saw that mechanical energy was conserved in the absence of nonconservative forces. In this lesson, we revise the definition of work as well as revise the idea that power is the rate of. The work energy theorem can now be rewritten by using the relations. Work done by force energy workenergy theorem lazy forces. Proving the workenergy theorem for a variable force is a little tricky. If the puck slides twice as far, the friction does twice as much negative work. Summary notes book pdf free download link book now.
Perfect for acing essays, tests, and quizzes, as well as for writing lesson plans. Class 11 physics revision notes for chapter 6 work. Work, energy and power class 8 science notes khullakitab. The best app for cbse students now provides work, energy and power class 11 notes latest chapter wise notes for quick preparation of cbse exams and school based annual examinations. Work is said to be done when the force is applied on a body and the body covers a certain distance. Class 11 physics revision notes for chapter 6 work, energy and power free pdf download. Workenergy theorem work, energy and power siyavula. It states that the change in the kinetic energy of a particle is equal to the work done on it by the net force. Potential energy, also referred to as stored energy, is the ability of.
The workenergy theorem can be derived from newton s second law. Work and kinetic energy lectures for university physics. The workenergy theorem states that the work done on an object by the net force is equal to the change in its kinetic energy. Work w is the energy transferred to or from an object by means of a force acting on the object. Physics notes class 11 chapter 6 work, energy and power work when a force acts on an object and the object actually moves in the direction of force, then the work is said to be done by the force. Check course website for lecture notes and announcement.
The workenergy theorem states that the work done by all forces acting on a particle equals the change in the particles kinetic energy. If youre seeing this message, it means were having trouble loading external resources on our website. Potential energy due to interaction with other objects today. Energy transformations falling water releases stored gravitational potential energy turning into a kinetic energy. Where k f is the final kinetic energy and k i is the initial kinetic energy. Every year there are 12 questions asked from this topic. Understand how the work energy theorem only applies to the net work, not the work done by a single source.
Work, power, and energy are among the most important concepts of mechanics. Work done by the force is positive if the angle between force and displacement is acute 0 notes on classical mechanics a work in progress daniel arovas department of physics university of california, san diego may 8, 20. Notes on workenergy theorem, principle of conservation of. Apr 21, 2015 download work energy theorem 21 april 2015 section a.
If a force is applied to an object at 90o to the motion of the object then that force does no work on the object. Also here the work done is the work done by all forces acting on the body like gravity, friction, external force etc. Equation 4 is the differential form of the workenergy theorem. Work energy theorem and it applications physics byjus. Workenergy theorem boundless physics lumen learning. Chapter 6 work, kinetic energy and potential energy. All books are in clear copy here, and all files are secure so dont worry about it. Home class9sciencenotes notes of ch 11 work and energy class 9th science 22 aug. Class 11 physics revision notes for chapter 6 work, energy. A summary of the workenergy theorem in s work and power. A variable force is what we encounter in our daily life. Workenergy theorem and energy conservation pdf book. Work energy transferred to or from an object by means of a force acting on the object. This is a theorem, ie a tautology because it is only true by definition of ke and by newton 2.
Download workenergy theorem and energy conservation book pdf free download link or read online here in pdf. In this case, one can define a potential energy for each of these forces. The work energy theorem states that the work done on an object by the net force is equal to the change in its kinetic energy. Engineering mechanics pdf notes em pdf notes smartzworld. Doubling the speed quadruples the kinetic energy so the work by friction to reduce the kinetic energy to 0 make it stop must also increase by a factor of 4. Here, youll learn about how its one of the most useful concepts in physics.
Work, energy, and power notes for iit jee, download pdf. It is important to know whether a force is an conservative force or an nonconservative force in the system, because this is related to whether the force can change an objects total mechanical. Proving the work energy theorem for a variable force is a little tricky. Work energy theorem study material for iit jee askiitians. This relationship between kinetic energy and work is called the work energy theorem. When a skier waits at the top of the hill before taking off, they have potential. In more general systems than the particle system mentioned here. The work done on an object is equal to the change in its kinetic energy. Jul 24, 2018 class 11 physics chapter 6 work, energy and power 03 work energy theorem iit jee neet duration. An example of a force that derives from a potential is gravitational force. The above derivation shows that the net work is equal to the change in kinetic energy. Summary notes book pdf free download link or read online here in pdf. Summary notes work work is done on an object when the object moves in the same plane as the force. Read online work energy theorem 21 april 2015 section a.
The work energy theorem states that the net work done on an object by the net force is equal to the change in kinetic energy of the object. Nov 29, 2017 in this article you will get cbse class 9 science, chapter notes on work and energy. It can also be defined as the rate of change of energy. Work done w is defined as the dot product of force f and displacement s. Jul 14, 2016 the net work done by the forces acting on a particle is equal to the change in the kinetic energy of the particle. Lecture 5 workenergy theorem and law of conservation of energy overview.
769 494 1646 244 184 247 467 766 367 1059 225 381 777 864 972 147 209 1086 1102 1592 1333 1087 695 1465 454 778 124 1339 826 916 215 397 345 131 155 858 163 1493